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The Effects of Common Electrolytes on Growth and Development of Selected Species of Aquatic Actinomycetes

Description: The role that aquatic actinomycetes play, in the production of tastes and odors in water supplies has been investigated since 1948. The ability of these organisms to produce by-products in lakes and streams, which renders the water unpalatable, is of considerable public health importance. It is desirable that the waterworks industry has as much information as possible concerning the factors that contribute to the growth of these organisms. Since it appears that the aquatic actinomycetes may be isolated from most fresh-water sources, the problem of diversified environments and nutritional requirements offers an excellent field of investigation. The fresh-waters of the world contain variable quantities of electrolytes that may determine in part the biological activity of these organisms. The unsolved questions in this instance are concerned with the electrolytes present and their quantitative effects on the growth and development of these forms.
Date: August 1959
Creator: Sissom, Stanley L.

A Study of a Selected Group of Science Related Characteristics of Non-Science Majors

Description: The purpose of this study is to gather information related to the characteristics of two groups of undergraduate non-science majors; namely, those students who once considered science as a career and subsequently changed to a non-science major and those who have never considered a career in science. It is frequently observed that children in the elementary school have an intense interest in science. One of the principal concerns of this study is how and for what reasons has the interest in science changed between elementary school and college? It is also the purpose of this study to gather information related to the attitudes of these college students toward the science courses they have had in high school and toward their science teachers. In attempting to arrive at an answer, the group who once considered a science career and those who have never considered an occupational choice in a field of science will be compared in the following areas: 1. General information such as sex, age, size of high school attended, rank within their graduating classes, college classification and military experiences. 2. Occupations and hobbies of parents. 3. Experiences which may influence attitudes toward science such as elementary school science, high school science courses, high school science teachers, attitudes toward science requirements, high school courses liked most, high school courses liked least, and membership in science clubs. 4. College science courses completed. 5. Extent of the interviewees' present interest in science, Finally, the circumstances surrounding the tentative choice of a science career by those who once considered such a career will be discussed.
Date: August 1957
Creator: Bearden, Bennie Paul

A Vegetative Key to the Grasses of Erath County, Texas

Description: "The orientation of this study began with a collection of the grasses of Erath County during their flowering periods. Collections were made in the Spring and Fall of 1950 and 1951 to obtain both vernal and autumnal grasses. Identifications were made from the grass floras previously mentioned and checked against specimens in the herbarium of North Texas State College for verification. In addition, the list was checked by W.A. Turney, Conservationist, United States Department of Agriculture of Dublin, Texas. Finally, the list was compared with that prepared by W.M. Cory for the plant areas of which Erath County is a part. On the basis of the above identifications, a critical study of the vegetative characteristics was made and a key based on these features prepared. The width of the blad and characteristics of the ligule, roots, culms, and sheaths were used to distinguish each of the eighty-six specimens found in the collection area. A drawing was made of the longitudinal section of the juncture of the blade and the sheath of each grass. This diagnostic section includes the collar, ligule, a part of the blade and sheath, and auricles, if present."-- leaf 5.
Date: August 1951
Creator: Robinson, Inez Evans

An Investigation of Naturally Occurring Tastes and Odors from Fresh Waters

Description: The Problem of the cause and control of tastes and odors in water supplies has been the subject of a great many investigations during the last half-century; however, many questions in this field remain to be answered. Theories relating to the cause of tastes and odors occurring in water are still rather numerous and, at present, only a few of them are compatible. Although several procedures have been employed for the eradication of tastes and odors from water supplies, none of them are completely successful.
Date: May 1955
Creator: Pipes, Wesley O'Feral, Jr.

A Vegetative Key to the Conspicuous Flowering Herbs of Denton County, Texas

Description: "The area of study was restricted to those common flowering herbs of Denton County, Texas, which have conspicuous flowers or a conspicuous flower cluster. There were, however, many plants included in this flora which are common to several counties of north-central Texas. Since there has been no previous key devised for the herbs of Denton County, Texas, the purpose of this key was to provide a flora which could be used by elementary and high school instructors, as well as any other interested persons who lack an extensive knowledge of botanical nomenclature." -- leaf iv.
Date: January 1957
Creator: Fate, Dwight Wesley

Toxicity Studies of Aquatic Actinomycetes

Description: Since Actinomycetes have been isolated from finished public drinking water, it is believed that the organisms are unaffected by the chlorination and flocculation of water treatment plants and pass as spores through the filters into the general distribution system. For this reason it was deemed imperative to study the toxic effects of these organisms.
Date: August 1952
Creator: Fair, Helena Juengermann

An Investigation of Selected Factors Related to the Professional Status of the Science Teachers in the Four-Year Accredited High Schools of Texas for the School Year 1952-1953

Description: The purpose of this study is to gather information related to the professional status of the science teachers in the four-year accredited high schools of Texas for the school year 1952-1953. The principal concern of the study is "Who is teaching science?"
Date: August 1953
Creator: Whitehead, Oren W.

Biological Indices of Stream Pollution

Description: A thorough biological survey and evaluation is a lengthy and expensive project. The number of technically trained persons required prevent its use by most public agencies. Since public health departments are the groups most frequently concerned with measuring the effects of pollution in streams, a need exists for a simplified method of sanitary survey. Recognizing this need, the Texas Health Department assigned the writer the problem of devising a method of survey which would require a field party of two and could be conducted entirely from a mobile field laboratory.
Date: August 1952
Creator: Russell, James C.

Microbial Utilization of a Certain Hydrocarbon Insecticide

Description: This problem includes, first, the isolation and identification of microorganisms which utilized the hydrocarbon insecticide as a sole source of carbon and energy; second, a determination of the effect on plants sprayed with the hydrocarbon medium as compared with the effect on plants sprayed with the hydrocarbon medium containing a good growth of hydrocarbon-utilizers; and third, a determination of the ability of laboratory stock cultures of organisms to utilize or remain alive in the hydrocarbon medium.
Date: August 1951
Creator: Dorman, Homer L.

Morphological and Physiological Changes in Micrococcus Pyogenes Var. Aureus during Development of its Resistance to Terramycin

Description: The problem in this investigation consists of, first, the procurement of several strains of Micrococcus pyogenes var. aureus; second, the comparison of the degree and rate of development of resistance of these organisms to terramycin; and, third, to study the morphological and physiological changes which occur during the development of resistance.
Date: August 1959
Creator: Watson, Gerald T.

A Rapid Modification of a Standard Disk-plate Antibiotic Susceptibility Test

Description: The objective of the work reported in this paper is one of a two-fold nature. The first objective is to develop a disk-plate sensitivity test that is more rapid than that of existing methods. The second requisite is that the materials, techniques, interpretation, and reporting of results be the sane as those required for the disk-plate method described in the Difco Manual.
Date: January 1955
Creator: Jackson, Leslie Warren

A Preliminary Report on the Effect of Roentgen Rays on the Formed Elements of Avian Blood

Description: This problem consists primarily in determining the numerical value of the leukocytes after different amounts of roentgen rays had been applied to the subjects. The Atomic Energy Commission set up a problem concerning the effects of roentgen rays on the fertility in chickens, and grants were given to two institutions to study this. The blood work in this paper was an off-shoot from one of these five fertility grants.
Date: August 1954
Creator: Berger, Gillett